package com.keshihao.springcloud.lbconfig;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * @Author Mr.Keshihao
 * @Date 2020/8/20 8:43
 * @Version 1.0
 */
@Component
public class MyLB implements LoadBalancer{

    private AtomicInteger atomicInteger = new AtomicInteger(0);

    public final int getAndIncrement(){
        int current;
        int next;

        do {
            current = this.atomicInteger.get();
            next = current >= Integer.MAX_VALUE ? 0 : current + 1;
        }while (!this.atomicInteger.compareAndSet(current,next));
        System.out.println("**********第几次访问，次数next: " + next);
        return next;
    }


    @Override
    public ServiceInstance instance(List<ServiceInstance> serviceInstances) {

        int index = getAndIncrement() % serviceInstances.size();

        return serviceInstances.get(index);
    }

}
